120 ESSENTIALS OF BACTERIOLOGY. 



Micrococcus Pyogenes Albus. (Kosenbach. ) Similar in every 

 respect to the pyogenes-aureus, except that it does not form a 

 pigment. 



Micrococcus Pyogenes Citrens. (Passet.) This staphylo- 

 coccus liquefies gelatine less rapidly than the pyogenes aureus, 

 and forms a citron-yellow pigment instead of the orange-yellow 

 of the aureus. 



Micrococcus Cereus Albus. (Passet.) Differs from the pyo- 

 genes albus in the form of colony. A white shiny growth like 

 drops of wax; hence the name cereus. It was found in pus, but 

 gave no action in animals. 



Micrococcus Cereus Flavus. (Passet.) A lemon-yellow 

 colored growth after a sbort time, otherwise not differing from 

 cereus albus. 



Micrococcus Pyogenes Tenuis. (Rosenbach.) 



Origin. Found in the pus of large inclosed abscesses. 



Form. Cocci, without any especial arrangement. 



Properties. Not much studied. 



Growth. It was cultivated on agar, on which it formed in 

 clear thin colonies ; along the needle-track an opaque streak, 

 looking as if varnished over. 



Bacillus Pyocyaneus. (Gessard.) 



Synonyms. Bacterium a3ruginosum, bacillus fluorescens. 

 (Schroter.) The bacillus of bluish-green pus. 



Origin. Found in 1882 in the green pus in pyocysemia. 



Form. Small slender rods with rounded ends, easily mistaken 

 for cocci. Often in groups of four and six, without spores. 



Properties. Very motile ; liquefy gelatine rapidly ; a peculiar 

 sweetish odor is produced in the cultures, and a blue pigment. 



Growth. Develops readily at ordinary temperature, growing 

 quickly and mostly on the surface ; it is an-obic. Colonies on gela- 

 tine plate. In two or three days a greenish iridescence appears 

 over the whole plate, the colonies having a funnel-shaped lique- 

 faction, and appearing under low power when still young, as 

 yellowish green, the periphery being granulated. - 



Stab Cultures. Mainly in upper strata, the liquefaction funnel- 

 shaped, the growth gradually settling at the bottom, a rich green 

 shimmer forming on the surface, and the gelatine having a deep 

 fluorescence. 



